Key bolt



Dec. 19, 1922. 1,439,63u

n J. F. NORTHEY.

KEY BOLT.

FILED DEC. i7, 1912i-- Ea- El.

- licult to keep a ,bolt absolutely tight unless.

Patented ller.. i9, lZZZ.

rre-i KEY Application led December yspecication.

This invention relates to bolts which are slotted so that a taper key may be employed to set up the bolt instead of a nut. Ordinarily y in such bolts the slot extends close to the end of the bolt and theback or" the taper key directly engages the end of the slot. Under such conditions it is diicult te drive the-key tight Without deforming thebolt owingY to the transverse frictional pressure exerted by the key against ythe outer end of the bolt,

. @which necessarily extends considerably beyond the support given by the parts through Which it passes. Further it isy extremely ditsome spring be provided between the bolt or its settlng-up means and the parts through Which it passes. such. for4 example, as the spring lock Washersused With ordinary rail- Ways bolts, which, however; are not adapted for use with key bolts. My object therefore is to vdevise means for reducingy the transverse pressure on Athe bolt-endduring the driving of the key to a minimum to provide the desired resilience in the setting up means for the bolt, and to attainthese results at ra minimum cost.

I attainmy object by means ot the constructions hereinafter described andillustrated in the accompanying drawings in Whieh- Y Fig. l is a side elevation of a bolt With the taper key and gib in position;

Fig. 2 a side elevation of the holt from a position at right angles to Fig. l; and

Fig. a cross section of the gib.

In the drawings like numerals of reference indicate corresponding parts in the different H gures. l

l is a key bolt. Which in essentials is the sameas the keybolt shown and described in United States Patent KNo.715266,35-3/1; dated May 14th, 1918. 2 ris the slot therein tor the passage of the key. 3 is the taper key. Heretofore it has been usual to drive this key between the end L of the slot and the parts Which the bolt `is employed to connect. In the improved construction the bolt and slot areso proportioned. that space is annu` Lenti. noarrrnr, or :resented ONTARIO. canape.

BOLT.

17, 1921. Serial N0.-523,1S9.

gib 5, the key 3 being` driven between the'` gib andy they parts which the bolt is used to connect. rThis gib is iormed withy shoulders 6 which engage the sides of the bolt and prevent longitudinal movement of thedgib when the taper key is in position. T he inner edge of the gib is preferably given a smooth finish and is tapered to correspond with the taper of the key 8. The contact-ing edges of the tapery key and gib are preferably givenfa smooth finish so as to reduce the lateral pressure tending` to bend the bolt end as much as possible. l iind that by employ- ,ing gib as` describedy that the key can be driven tightly Without springing or bending the bolt end'.

To give the desired resiliency referred to in the preamble of this specification, the inner face of the gib is concaved or archedas shown, so that the Agib contacts with the back of the taper key only at its ends7 .these 'contacting' surfaces being spacedf'lirem the vlsides ot the bolt soithat the gib forms in eti'eetr an arch loaded at the center and supy ported at each end. p

si certain amount of friction is desirable to tendi--tofprexentthe taper key backing up, While it fis desirable also that it should be possible to lit the gib in Aposition with as little f trouble as possible. 1 l therefore' sol proi'iortion the slot, thenib and the taper key that the `ib Will fit loosely in the slot. While there vis a tight fit between the sidesl ol the taper key and the sides olz the slot` This is best effected by making the tapered key and the gib of the samegauge material7 While the outer part of the slot isslightly increased in Width, as shown particularly in Fig: 2. The Igib is thus easily slipped into place. lllhen the taper key is driven there is friction between the sides of the slot and y the sides ol' the key., between the inner edge. of the key and the part through which the bolt passes, and further frictional resistance between the ends of the gib and the outer edge ofthe key This friction is suiiicient under all ordinary conditions to prevent the key backing' out, while it 'is always possible to deforn'l the end of the key after it has been driven to give added security.

ioo

It isalso desirable to so apply the pressure j of the back of the gib to the end of the bolt that this pressure tends to contract the sides of the slot of the bolt rather than otherwise.

I therefore round the back of the gib transsection ot the median plane of the slot witlt the end ol the bolt, or at least so that the pressure is not concentrated on the parts ot the end adjacent the sides of the slot. :By

thus rounding the back of the gib I {ind that a tendency exists to contract the sides oft 1the slot and this increases the friction of the sides or". the slot against the sides of the taper key.

lit shouldbe noted that frictional contact between the sides ot the taper-keyand the sides of the slot is not objectionable in any way, as any transverse kpressure tendingr to bend the `bolt end is exerted close to fthe part through which the bolt passes., and con sequentlyresistance to bending is at av maxnnum.

What I cla-im as my invention is :-d

l. i slotted bolt inL combination with a taper key and a gib adapted to .t in 'the slot7 the gib being shouldered `at the back for engagement withthe end of the `bolt at opposite sides thereof and having itsy front edge tapered and conc-aved so thatV its surfaces of contact with the key are spacedfroinvthesides of the bolt, the gib thus forming in f effect an arch loaded at the center andsupported at each end. l

Q. A. slotted bolt in combination with a taper key and a gib adapted to fit in the slot7 the gib being shouldered at the back vior ei'igagement with'the end of the bolt att-"oppor arch loaded at the center and supported at each end.

3.1i slotted bolt in; combination with a gib looselywiitting between :the sides oil the fthe end of the bolt at opposite sides thereof and having its front edge tapered and conca-Ved sothatl its: surfaces of contact with the key are spaced from the sides of the belt, the gib thus forming i1i.eiieet an arch loaded f at `the center-andy supported at each end.

at. Afslotted bolt incombination with a loosely tltting'betw-een'thesides oi the -slotadjacent its outer end and a taper'key fitting 'tightly-between the sidesot theslot remotef fromf'the outer end, the gib being shouldered at the back for engagement/with the end of the'boltfat opposite sides-thereof,

vcenterand supported at eachfend.

I JfAslottedlboltL-in combination with a taper key and'afgib'adapted-to it in the slot,

' the gib g being shouldered at the l back for engagement with the lend 'of the bolt at oppositeC sides thereof, wthe back of thegibbctween ythe shoulders #being transversely rounded and the front 'edgeof the gibitapered. 6.'- A slotted bolt in combination with a-gib loeselyitting between the sides of 'the slot adjacent its outer endf and aftaperkeylitting tightly between the sidesof-the slot remote lfrom the outer end,'thegibbeingshouldered latthe back for engagement with the end of the bolt at opposite sides'thereofand-having its front edge tapered.

` Signed 'at Toronto, Canadzuthis 25th lday of'November, 1921. f

JOHN PELLl 'NQRTHEY 

